A Practical Report of Oculomotor Response in Collegiate American Football Players

Abstract

Subconcussive head impact in sports is a complex public health issue. Near point of convergence (NPC) values have shown to reflect subclinical neuronal damage; however, the longitudinal pattern of NPC changes in association with subconcussive head impact remains unclear. This prospective longitudinal study examined the NPC response in a single Japanese collegiate American football season through a series of repeated measurements. This prospective longitudinal study of Tokai Collegiate American Football Association Division 1 players included baseline measurements of NPC and 2 preseason practices and 2 in-season games. Outcome measures were obtained for each time (a total of 9 points). The 33 included players were all men, with a mean±SD age of 19.8±1.2 years. There was a significant difference in NPC values from baseline to post-game 2; p<0.001. Relative to baseline (mean±SD NPC: 5.90±2.16 cm), NPC values were significantly increased at post-practice 1 (7.99±2.57 cm; p<0.001), pre-practice 2 (7.29±2.57 cm; p<0.001), post-practice 2 (8.03±2.40 cm; p<0.001), post-game 1 (7.09±2.41 cm; p<0.01), and post-game 2 (7.18±2.15 cm; p<0.01). This longitudinal case study suggests that Japanese collegiate American football players experienced changes in NPC as the competitive season progressed. The oculomotor system may have an adaptive capacity to subclinical head impact, regardless of race or ethnicity; nevertheless, the mechanism for such an adaptive capacity remains an open question and warrants further investigation.